I'm tasked to fix a frontend system for approving/disapproving database updates, it's made in PHP and Postgres as it's Database.

The system goes like this:

The user updates his currently existing db entry using the system, the changes are applied to the db entry and flagged it's status to "Modified". Approving that entry won't be a problem 'cause when the admin approves that request the system will flag that entry as "Approved". The problem is the disapproval of that update, the new changes must be deleted and must revert back to the old entry, but that's not possible 'cause the original entry has already been modified.

How do I go about this? I thought of backing up the original entry to be updated and restore it to the database only if the admin disapproves the new changes. But this means creating another set of tables to the database just for that backup ... I wonder if there's a better way?

Here's a small diagram of my idea...:
http://img57.photobucket.com/albums/...disapprove.png

You need a new set of tables. How many - it depends on what you'd liek to backup. But you may handle the problem from the other way - the onld entry stays in the table until the new one (from an extra table) is approved.
I don't know how you picure looks like, as it doesn't display, so maybe you just have the same idea.

Thanks for the advice, that's exactly what I was thinking. Each entry takes a lot of tables though ...

I had a problem similar to this. I was writing a link submission program where people could simply fill out a form and submit their link to my site. The main problem with it was that people could submit inappropriate sites. So, I added a little approve/disapprove routine where the information the user entered was sent to my inbox in an HTML formatted email that included a form that I could submit to the database.

Here's how it worked:

-- linknow.php

Here is where the user enters the information about the site he/she wishes to link. The form is submitted to submitlink.php

-- submitlink.php

This script formats and sends an HTML email that includes the form from linknow.php, with each text field/area filled with the information the user entered (all passed through POST vars). Nothing is placed into the database.

-- my email inbox

When I receive the email, I can edit each of the entries directly by simply changing the values in the text boxes then clicking submit. The form submits to a script I placed in an admin directory. This script puts the information into the database.

You may be able to do something similar, depending on how your system is set up. This way, nothing gets changed in the database before you approve/disapprove. The only problems, I suppose, are that the information would have to be POSTed several times and that my idea requires HTML emails (rather than a slick admin site) to do approving/disapproving.

Just an idea. Good luck!

Interesting solution, I'll keep that in mind. Thanks